The Race to Build a Solar House That Anyone Can Afford

The Department of Energy's Solar Decathalon challenges students to make energy-efficient yet affordable homes.

Water splashed from rooftop of the almost-finished house and into the rainwater garden, which soon would have plants but for the moment was just an empty trough. Carly Berger tilted her helmeted head back and called, “What are you doing up there?”

Another head popped out from over the roof’s edge. “I’m cleaning out the gutters!”

Inside, the systems guys crowded into the front hallway, finishing work on the super-efficient ventilation that will keep the house hot or cool by transferring heat between outgoing and incoming air. Saws created a constant hum in the background. Berger, a masters student in architecture at Parsons The New School for Design, had sawdust strewn across her back.

She and other students working on the project, dubbed the Empowerhouse, were frantically trying to finish construction in time for a celebratory party scheduled for that night. The white party tents already sat next to the house, in a lot on the Stevens Institute of Technology campus, just across the Hudson River from New York City. But they had a couple of more days to finalize things, Berger said, before they had to partially dismantle the house and ship it down to Washington, D.C., for the Department of Energy’s biannual Solar Decathalon competition.

Since 2002, the federal government has invited competitors from schools around the world to bring their energy-efficient, attractive, solar-powered concept houses to the National Mall. This year’s competition will take place in September and includes a new category in which teams can compete: “affordability.”

The Empowerhouse team, which includes students from Parsons, the Stevens Institute, and the Milano School of International Affairs, Management, and Urban Policy, made a low price point a focus of their project. They receive full points if construction costs come in at or below $250,000. But the team’s ambitions go beyond snatching up those 100 points, just one-tenth of a perfect score. The team has partnered with Habitat for Humanity and the D.C. Department of Housing and Community Development to give its competition house, expanded into a two-family home, a permanent place in the neighborhood of Deanwood, east of the Anacostia River.

The Empowerhouse team isn’t the only intending to pass on its product. Purdue's team is looking for a family to take over its INhome house, which, apart from the solar panels, is meant to look like any other Indiana home. Ohio State’s enCORE will spend a year on the university’s campus but eventually will relocate to a low-income neighborhood. A few houses from past competition have found similar situations: a house designed in 2009 by a team of students from Boston Architectural College and Tufts University anchored a project that provided housing for formerly homeless and low-income families, and the University of Texas donated its 2005 house to a local community development corporation. But most competition houses end up back on the campuses where they were built to serve as educational exhibits, office space, or student housing.

Because the Empowerhouse team knows its building will house a real family and wants it to serve as a model of affordable green housing for groups like Habitat for Humanity, the students' concerns go beyond the contest guidelines. They included the large, shady front porch because they observed that sitting outside and chatting with neighbors is a major aspect of social life in Deanwood. And the team focused on using building materials accessible to anyone.

“It was really important to us that we used readily available products,” the type anyone could find at Home Depot or Lowe’s, Berger says. “That’s the reality of most homes.”

The Empowerhouse team has also spent time working closely with the community. Heather Zanoni, who studies urban policy at Milano, has been making multiple trips to Washington each month to meet with a slew of community and government organizations. She’s been surprised, she said, how well the D.C. government agencies she’s been meeting with are working together.

Within the next two weeks, the team will split their house into two, load it onto trucks, and ship it to the National Mall for the start of competition on September 24. Once the contest concludes, the house will move to Deanwood. A crew will add a second story with additional bedrooms and place it next door to a similar home. It won’t be Deanwood’s only energy-efficient home: through CarbonfreeDC, some houses in the community have been retrofitted. But since it’s built according to Passivhaus principles and should generate all the energy its occupants need, the Empowerhouse will go one step further, saving its occupants an estimated $2,300 each year in energy bills.

photos: top by Sarah Laskow, bottom via Vasilis Kyriacou